An operation by British forces in southern Iraq to root out death squads and extend civic control in the city of Basra has hit political problems and resulted in a series of retaliatory attacks, The Independent on Sunday has learned.

About 1,000 British soldiers are taking part in Operation Sinbad, seen as a crucial test of the ability of the UK-led multinational force (MNF) in southern Iraq to "clean up" the country's second-largest city. Working with about 2,300 Iraqi troops, the aim is to cordon off areas of Basra one by one, take over police stations infiltrated by "rogue elements" and allow contractors to carry out quick projects aimed at boosting public confidence, such as repairing street lights and clearing rubbish.